use is for identical object comparison
diff --git a/tests/primitives/test_hashes.py b/tests/primitives/test_hashes.py
index 07e2d8e..4651770 100644
--- a/tests/primitives/test_hashes.py
+++ b/tests/primitives/test_hashes.py
@@ -52,7 +52,7 @@
         This test assumes the presence of SHA1 in the default API.
         """
         h = hashes.SHA1()
-        assert h._api == _default_api
+        assert h._api is _default_api
 
 
 class TestSHA1(object):